Objective:

2

To investigate the effects of ethanol extract of

Patrinia scabiosaefolia

(EEPS) on chemo-resistance of colorectal cancer cells (CRC) and explore the possible molecular mechanisms.

Methods:

2

5-fluorouracil (5-FU)-resistant human colorectal carcinoma cell line (HCT-8/5-FU) and its parental cells HCT-8 were treated with EEPS (0

0.25

0.50

1 or 2 mg/mL)

or 5-FU (0

100

200

400

800 or 1600 μmol/L). The 3-(4

5-dimethylthiazol-2-yl)-2

5-diphenyltetrazolium bromide (MTT) assay was performed to evaluate the cell viability. Cell density was observed by phase-contrast microscope

cell counting and colony formation assay were used to determine the cell proliferation of HCT-8/5-FU cells treated with 0

0.5

1 or 2 mg/mL EEPS. Cell apoptosis was determined by Hoechst staining. Western-blot was performed to detect the phosphorylation of AKT as well as the protein expression level of B-cell CLL/lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (Bax).

Results:

2

Compared with HCT-8 cells

MTT assay results indicated that HCT-8/5-FU cells were resistant to 5-FU treatment (

P

<

0.05)

and sensitive to EEPS treatment (

P

>

0.05). Moreover

compared with untreated HCT-8/5-FU cells

1 and 2 mg/mL of EEPS treatment significantly reduced cell density

cell number

inhibited cell survival (

P

<

0.05)

and induced apoptosis in HCT-8/5-FU cells. Furthermore

1 and 2 mg/mL of EEPS significantly decreased the phosphorylation level of p-AKT and Bcl-2 protein expression

and increased the expression of Bax protein (

P

<

0.05).

Conclusion:

2

EEPS is a promising therapeutic agent that may overcome chemo-resistance in cancer cells

likely through suppression of the AKT pathway and promotion of cancer cell apoptosis.